후면 형상에 따른 결정질 실리콘 태양전지의 후면전계 형성 및 특성

김현호,김성탁,박성은,송주용,김영도,탁성주,권순우,윤세왕,손창식,김동환,Kim, Hyun-Ho,Kim, Seong-Tak,Park, Sung-Eun,Song, Joo-Yong,Kim, Young-Do,Tark, Sung-Ju,Kwon, Soon-Woo,Yoon, Se-Wang,Son, Chang-Sik,Kim, Dong-Hwan 한국재료학회 2011 한국재료학회지 Vol.21 No.5

To reduce manufacturing costs of crystalline silicon solar cells, silicon wafers have become thinner. In relation to this, the properties of the aluminium-back surface field (Al-BSF) are considered an important factor in solar cell performance. Generally, screen-printing and a rapid thermal process (RTP) are utilized together to form the Al-BSF. This study evaluates Al-BSF formation on a (111) textured back surface compared with a (100) flat back surface with variation of ramp up rates from 18 to $89^{\circ}C$/s for the RTP annealing conditions. To make different back surface morphologies, one side texturing using a silicon nitride film and double side texturing were carried out. After aluminium screen-printing, Al-BSF formed according to the RTP annealing conditions. A metal etching process in hydrochloric acid solution was carried out to assess the quality of Al-BSF. Saturation currents were calculated by using quasi-steady-state photoconductance. The surface morphologies observed by scanning electron microscopy and a non-contacting optical profiler. Also, sheet resistances and bulk carrier concentration were measured by a 4-point probe and hall measurement system. From the results, a faster ramp up during Al-BSF formation yielded better quality than a slower ramp up process due to temperature uniformity of silicon and the aluminium surface. Also, in the Al-BSF formation process, the (111) textured back surface is significantly affected by the ramp up rates compared with the (100) flat back surface.

용매추출-전해채취법에 의한 망간단괴 매트상 모의 침출용액으로부터 코발트 회수

김현호,남철우,박경호,윤호성,김민석,김철주,박상운,Kim, Hyun-Ho,Nam, Chul-Woo,Park, Kyung-Ho,Yoon, Ho-Sung,Kim, Min-Seuk,Kim, Chul-Joo,Park, Sang-Woon 한국자원리싸이클링학회 2016 資源 리싸이클링 Vol.25 No.2

망간단괴 매트상 모의 침출용액에서 구리 용매추출과 수산화 침전법에 의해 구리와 철이 제거 된 용액(Co 1.91 g/L, Ni 14.65 g/L)으로부터 용매추출-전해채취 연속공정을 통해 코발트를 분리, 회수를 위한 규모확대 실험(망간단괴 기준 380 kg/day)을 수행하였다. 용매추출의 경우 추출제로는 NaOH로 45% 비누화 된 0.22 M Cyanex 272, 세정용액은 코발트 2 g/L(pH : 3.0), 탈거용액은 코발트 전해폐액(Co 36.0 g/L, $Na_2SO_4\;70g/L$, pH : 1.5)을 사용하였으며, 탈거된 유기상은 산과 증류수의 세척 공정을 통해 재사용하였다. 추출단, 세정단 그리고 탈거단의 O/A 비는 각각 1/1.5, 10/1 그리고 1.5/1 이었으며, 산세척과 수세척단의 O/A 비는 각각 1/1, 6/1이었다. 용매추출공정의 코발트의 추출율과 탈거율은 각각 99.8%와 99.88%이었으며 탈거액의 코발트와 니켈의 농도는 각각 40.27 g/L, 4 ppm이었다. 전해액의 pH 조절을 위해 전해폐액 순환 방식을 도입한 전해채취공정은 $0.563A/dm^2$의 전류밀도에서 67.0%의 전류효율을 나타내었으며, 99.963% 순도의 금속 코발트를 얻었다. A scale up tests (380 kg/day) using a continuous solvent extraction and electro-winning system was carried out to separate and recover cobalt from a solution containing 1.91 g/L Co and 14.65 g/L Ni. The solution was obtained during a process including solvent extraction and precipitation stages for removal of Cu and Fe from a synthetic sulfuric acid solution of manganese nodule matte. The optimal condition for solvent extraction was : solvent concentration of 0.22M Na-Cyanex 272 (45% saponified with NaOH) and O:A phase ratios of 1:1.5, 10:1 and 1.5:1 used in extraction, scrubbing and stripping stages, respectively. The extraction and stripping efficiencies were found to be 99.8% and 99.88%, respectively. The stripped solution contained 40.27 g/L Co with 4 ppm Ni. Cobalt metal of 99.963% purity was yielded with current efficiency of 67% and current density of $0.563A/dm^2$ during the electro-winning process.

망간단괴 매트상 모의 침출용액으로부터 용매추출-전해채취 공정에 의한 구리의 회수

김현호,박경호,남철우,윤호성,김민석,김철주,박상운,Kim, Hyun-Ho,Park, Kyung-Ho,Nam, Chul-Woo,Yoon, Ho-Sung,Kim, Min-Seuk,Kim, Chul-Joo,Park, Sang-Woon 한국자원리싸이클링학회 2016 資源 리싸이클링 Vol.25 No.1

망간단괴 매트상 침출액 조성으로 제조 된 모의 용액(Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L)으로부터 용매추출-전해채취 연속공정을 통해 구리를 분리-회수하기 위하여 규모 확대용 용매추출장치인 6단 혼합-침강기(mixer-settler : 추출 4단, 탈거 2단)와 전해조를 이용하였다. 용매추출의 경우 추출제로는 40%(v/v)의 LIX 84I, 탈거용액은 전해폐액(Cu 35.0 g/L, $H_2SO_4$ 180 g/L)을 사용하였으며 추출단과 탈거단의 O/A 비는 각각 1/1과 1.5/1 이었다. 용매추출공정의 구리의 추출율과 탈거율은 각각 96.7%와 91.0%이었으며 탈거액(전해액)의 구리, 니켈, 코발트 그리고 철의 농도는 각각 50~51 g/L, 25 ppm, 5 ppm 그리고 3 ppm 이었다. 전해채취공정은 $1.50A/dm^2$의 전류밀도에서 98.9%의 전류효율을 나타내었으며, 99.833% 순도의 금속 구리를 얻었다. A scale-up test with a continuous solvent extraction and electro-winning system was carried out to separate and recover copper from a synthetic sulfuric acid solution (Cu 10.5 g/L, Co 2.0 g/L, Ni 15.0 g/L, Fe 0.2 g/L). The solution was introduced into mixer-settlers with four stages of extraction and two stages of stripping for continuous countercurrent solvent extraction to separate copper from nickel and cobalt. The loading was carried out using 40% LIX 84-I(v/v) as extractant with a phase ratio of A : O = 1 : 1. Meanwhile, the stripping was undertaken at a phase ratio of A : O = 1 : 1.5 using depleted electrolyte containing 35.0 g/L Cu and 180 g/L $H_2SO_4$ as stripping solution. The extraction and stripping efficiencies were found to be 96.7% and 91.0%, respectively. The copper composition of the stripped solution (pregnant electrolyte) was 50.0 g/L Cu with impurities of 25 ppm nickel, 5 ppm cobalt and 3 ppm iron. In the electro-winning process, copper metal of 99.833 purity was yielded with current efficiency of 98.9% and current density of $1.50A/dm^2$.

요추(腰椎) 추간판(椎間板) 탈출증(脫出症)으로 인하여 발생한 소음인(少陰人) 요각통(腰脚痛) 치험 1례

김현호,김은이,김경선,임은철,정경숙,윤형선,Kim, Hyun-Ho,Kim, Eun-Yi,Kim, Kyung-Sun,Lim, Eun-Chul,Jung, Kyung-Suk,Yoon, Hyoung-Seon 사상체질의학회 2004 사상체질의학회지 Vol.16 No.3

1. Objectives The purpose of this study is to give an account of the effects of Korean herbal medicine therapy which is based on the Sasang Constitutional Medicine for the patient who has suffered from low back pain caused by the Herniated Lumbar Disc. 2. Methods Consulting her sungjeong(性情), Chehyungkisang(體形氣像) and QSCCII, we have diagnosed her as Soeumin(少陰人), and have prescribed Hyangbujapalmul-tang(香附子八物湯). 3. Results After the treatment, she felt her symptoms, low back pain, headache, and general condition, improved. 4. Conclusions This paper describes the process of management and changes of symptoms. We hope this paper useful to rehabilitatable treatment for low back pain caused by the Herniated Lumbar Disc through Sasang Constitutional Medicine.

Variation of Grain Traits in Landraces of Rice Collected from Vietnam

김현호,조재성,Kim, Hyun-Ho,Jo, Jae-Seong Institute of Agricultural Science 1997 Korean Journal of Agricultural Science Vol.24 No.2

베트남으로부터 수집된 총 437 벼 지역종을 사용하여 총 종자 단백질을 분석하기 위하여 SDS-PAGE와 phenol 반응을 수행하였다. 세 가지 다른 형태의 glutelin a subunit이 검출되었다. 60kDa의 분자량인 wx 단백질 수준은 세 그룹으로 분리되었는데, 이는 non-glutelin, intermediate, 그리고 glutelin 전분 유형이다 종자 저장 단백질과 wx 단백질의 변이에 의한 실험결과 지역종은 7그룹으로 구분된다. Glutelin a subunit의 A와 B형의 빈도분포는 벼 지역종이 수집된 위도에 따라서 변하였다. 페놀 반응에 대한 지리학적인 구배가 검출되었다. A total of 437 landraces of rice from Vietnam were analyzed for total seed protein by SDS-PAGE and phenol reaction. The different types of glutelin $\alpha$ subunits were detected. The level of wx protein with 60kDa molecular weight was divided into 3 groups, corresponding to non-glutinous, intermediate and glutinous starch types. Based on the variation in seed storage protein and wx protein, landraces were classified into 7 groups. Frequency distribution of types A and B of glutelin $\alpha$ subunits changed with the latitude at which rice landraces were collected. Geographical cline for phenol reaction was detected.

대학생들을 대상으로 한 슬링을 이용한 교각운동이 큰볼기근과 척추세움근 근활성도에 미치는 영향

김현호,Kim, Hyun-ho 대한정형도수물리치료학회 2020 대한정형도수물리치료학회지 Vol.26 No.2

Background: This study demonstrate the effect of bridge exercise using sling device on the improvement of gluteal maximus and elector Spine EMG (electromyogram) in college student. Methods: 30 college students participated in this experiment and received bridge exercise using sling device for 30 minutes a day for four weeks. Results: The effects of bridge exercise using sling device were evaluated by measuring the muscle activation on gluteal maximus and elector spine. The differences between pre-test and post-test in G-max (p<.05) and right elector spine (p<.05) were significant. The difference between in G-max left and right side was not significant both before (p<.05) and after (p<.05) bridge exercise using sling. The difference between in elector spine left and right side was not significant before bridge exercise using sling (p<.05) but after bridge exercise using sling (p<.05). Conclusion: The results indicated that bridge exercise using sling device improved gluteal maximus and elector spine EMG. This study demonstrated the effectiveness of this new approach and provided a good guide to improve gluteal maximus and elector spine EMG.

따뜻한 백색 LED의 제조를 위한 Sr₃SiO₅:Eu²⁺ 형광체에서의 융제 첨가 영향

김현호,정강섭,이승원,김병규,Kim, Hyun-Ho,Chung, Kang-Sup,Lee, Seoung-Won,Kim, Byoung-Gyu 한국세라믹학회 2012 한국세라믹학회지 Vol.49 No.1

In this paper, a yellow phosphor $Sr_3SiO_5:Eu^{2+}$ that emits efficiently at the 450 nm excitation for warm white LED is studied. In addition, the effects of various flux $BaF_2$, $NH_4Cl$ on the emission spectra were investigated. The samples were synthesized through conventional solid state reaction under reducing atmosphere of 95% $N_2$-5% $H_2$ mixture at the high temperature. All phosphors showed a excitation band from 450 nm and broad band emission peaking at region of 580 nm. The optimal concentration of $BaF_2$ flux is 3 wt% for $Sr_3SiO_5$ with doping 0.05mol Eu phosphors fired in a reductive atmosphere. The phosphor showed highest emission peaking at 582 nm.

결막이완증에서 지짐술과 봉합술의 병행효과 4예

김현호,신동수,이규원.Hyun Ho Kim. M.D.. Dong Su Shin. M.D.. Kyoo Won Lee. M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.5

Purpose: We performed cauterization and suturing without resection and evaluated the technique`s efficacy in the treatment of conjunctivochalasis. Methods: Four eyes of three patients diagnosed with conjunctivochalasis were treated with cauterization and suturing. After opening the eyelids, the loosened bulbar conjunctiva was pulled down tensely. After local anesthesia near the inferior fornix (about 8 mm below the limbus), the bulbar conjunctiva and Tenon`s capsule were gripped together by bipolar cautery (UM 150A). The cauterization was performed in one second. Still gripped by the bipolar cautery, the bulbar conjunctiva and Tenon`s capsule were fixed to the sclera with Vicryl 6-0. Identical procedures were performed on two other sites along the inferior fornix. The suture stitch were removed 10 days after the surgical procedure. Results: The objects were 4 eyes of 3 patients (1 male, 2 females with an average age of 63 years). The mean follow-up period was 4 months. There were no recurrences or any postoperative complications caused by cauterization. Conclusions: We successfully treated conjunctivochalasis with a simple procedure of conjunctival fixation to the sclera through cauterization and suturing.

이중합성 교량의 복합스터드 전단연결부의 정적강도 평가

김현호,심창수,윤광중,이필구,Kim, Hyun Ho,Shim, Chang Su,Yun, Kwang Jung,Lee, Pil Goo 한국강구조학회 2005 韓國鋼構造學會 論文集 Vol.17 No.5

철도교는 강성이 주요한 설계인자이기 때문에 기존의 2거더 교량의 구조적 효율성을 높이기 위해서 이중합성 구조를 가진 철도교를 제안하였다. 일반적으로 강합성 연속교를 설계할 경우, 부모멘트 구간에 존재하는 콘크리트 바닥판은 인장에 저항하지 못한다고 가정하고 바닥판 단면을 무시하게 된다. 부모멘트 구간에서는 합성단면의 강성이 감소하게 되므로 이를 보완하기 위해 강재단면이 커지게 되는데, 이러할 경우 변단면의 적용이 불가피하게 되고 강합성형으로서의 장점이 반감된다고 할 수 있다. 이와 같은 문제점을 해결하기 위한 다양한 접근법이 존재하지만 그 중에서도 경간을 확대하고 강성이 중요한 설계인자가 되는 경우에 적절하게 사용될 수 있도록 제안된 교량의 형태가 이중합성구조이다. 따라서 본 연구에서는 이중합성 전단연결부의 거동을 파악하기 위하여 수평스터드, 수평스터드와 수직스터드가 함께 배치된 복합스터드 부재에 대한 push-out 실험을 수행하였다. 실험결과의 분석을 통하여 기존의 설계식과의 비교를 수행하고 정적 거동을 평가하였다. A railway bridge with a double composite section is proposed to enhance the structural performance of existing two-girder bridges because the governing design parameter of railway bridges is the flexural stiffness. The concrete deck in negative moment regions is neglected in the design of continuous composite bridges assuming the concrete slab has no resistance to tension. Therefore, the flexural stiffness of the composite section in the negative moment region is reduced resulting in the increase of the depth of the steel section. In order to resolve this disadvantage, several methods are suggested and the double composite section is one of the excellent solutions for extending the span length and increasing the flexural stiffness. In this study, push-out tests on lying studs and mixed stud shear connection with lying and vertical studs were performed to investigate the behavior of the shear connection in the double composite section. Static strength of the shear connection was evaluated through the test results and numerical analyses.

눈물점마개를 이용한 눈물샛길의 치료

김현호,정병진,신동수,이규원,Hyun Ho Kim,Byung Jin Jeong,Dong Su Shin,Kyoo Won Lee 대한안과학회 2007 대한안과학회지 Vol.48 No.4

Purpose: To evaluate the results and complications of the punctal plug insertion through lacrimal fistula. Methods: Four patients diagnosed with congenital lacrimal fistula had a punctual plug inserted through the lacrimal fistula without anesthesia from January to May 2005. Results: Mean follow-up period was 6.8 months. In two pediatric patients whose mean age was 5.0 years, the fistula was not associated with nasolacrimal duct. In two adult patients, it was associated nasolacrimal duct obstruction, whose mean age was 49.0 years. In all cases epiphora improved. There was a puncal plug prolapse in one case and no other complications. Conclusions: Punctal plug insertion is considered a simple and useful technique for lacrimal fistula without congenital nasolacrimal obstruction in children especially whose parents refuse general anesthesia. Punctal plug insertion can be useful to reduce scarring in adult patients that receive endoscopic dacryocystorhinostomy with nasolacrimal obstruction.